1. Field of the Invention
This invention relates to a centering device, in particular for steering valves in motor vehicles. In steering gears with a centering device, there are provided a drive part and a power takeoff part, and these parts are connected with each other by means of a torsion bar and are elastically rotatable against each other. The drive part is made in sleeve-fashion and encloses the torsion rod. The power takeoff part again partly encloses the drive part.
2. Description of the Prior Art
Such a centering device can be used advantageously for steering valves in the rotary slide or rotary piston design. EP0244449 contains a model based on this design. This centering device reveals a metallic shock absorber with axial spring action that is attached to the drive part and that acts upon the power takeoff part via a mid-position catch device with prestress. The mid-position catch device consists of the oblique surfaces associated with the two structural parts with roller bodies in between. In this way, one gets, on the drive part, a resetting force that depends on the twisting of the two structural parts and that is added to the twisting force of the torsion bar. The mid-position catch device here primarily takes care of the exact centering of the two structural parts that can be rotated against each other. This mid-position catch device needs an axial and radial installation space mostly on account of the metal shock absorber. Besides, this device requires a comparatively high production effort because one must fasten a centering piece and an end piece to the shock absorber and a centering piece on the power takeoff part.
The task of the invention is to find a centering device combined with a torsion bar that can be made at reasonable cost with a very small axial space requirement.
This problem is solved by the centering device of the present invention. Other more preferred embodiments are also disclosed.